Yamaha RD125 (1979-80)

The Yamaha RD125 motorcycle was manufactured in 1979 and 1980. The bike is powered by a two-stroke, parallel twin engine, with a capacity of 124cc. The air-cooled engine has a bore x stroke of 43×43 mm and a compression ratio of 6.8:1. The induction system includes two 18mm Teikei carburetors and uses battery coil ignition. The bike is started with a kick. The maximum power output produced is 17 hp / 12.4 kW at 8500 rpm, and the maximum torque is 1.3 kgf-m at 8000 rpm. The five-speed transmission drives the bike using a chain final drive with a gear ratio of (1) 34.52 (2) 19.67 (3) 14.11 (4) 11.34 (5) 9.11. The steel tube frame has an engine used as a stressed member, while a 28 mm telescopic fork and dual rear shocks adjustable for preload provide suspension. The bike has a single 240mm disc brake on the front and a 130mm drum brake on the rear. The front and rear tires are 2.75-18 and 3.00-18, respectively. The wheelbase is 1245 mm / 49.0 in, with a seat height of 749 mm / 29.5 in. The bike weighs 115 kg / 255 lbs, and its fuel capacity is 11.5 Litres / 3.04 US gal.

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Technical specifications:

Make Model: Yamaha RD 125

Year: 1979 – 80

Engine: Two stroke, parallel twin

Capacity: 124 cc / 7.6 cu-in

Bore x Stroke: 43 43 mm

Cooling System: Air cooled

Compression Ratio: 6.8:1

Induction: 2x 18mm Teikei carburetors

Ignition: Battery coil

Starting: Kick

Max Power: 17 hp / 12.4 kW @ 8500 rpm

Max Torque: 1.3 kgf-m @ 8000 rpm

Transmission: 5 Speed

Final Drive: Chain

Gear Ratio: (1) 34.52 (2) 19.67 (3) 14.11 (4) 11.34 (5) 9.11

Frame: steel tube engine used as a stressed member

Front Suspension: 28 mm telescopic forks

Rear Suspension: Dual rear shock pre-load adjustable

Front Brakes: Single240mm disc

Rear Brakes: 130 mm Drum

Front Tyre: 2.75-18

Rear Tyre: 3.00-18

Wheelbase: 1245 mm / 49.0 in

Seat Height: 749 mm / 29.5 in

Wet Weight: 115 kg / 255 lbs

Fuel Capacity: 11.5 Litres / 3.04 US gal